Atmospheric pressure (millibars) Altitude (kilometers) 200 400 600 800 1,000 120 75 Temperature 110 Pressure 65 100 Thermosphere 90 55 Mesopause 80 Heating via ozone Mesosphere 45 70 Altitude (kilometers) 60 Altitude (miles) Stratopause 35 50 Stratosphere 40 25 30 Tropopause 15 Ozone “layer” 20 Heating from the earth Troposphere 10 5 Figure 17-2 Page 419 Pressure = 1,000 millibars at ground level (Sea Level) –80 –40 40 80 120 Temperature (˚C)

Altitude (kilometers) Ozone concentration (ppm) 40 25 35 20 Stratosphere 30 25 Stratospheric ozone 15 Altitude (kilometers) 20 Altitude (miles) 10 15 10 5 Troposphere 5 Photochemical ozone Figure 17-3 Page 420 5 10 15 20 Ozone concentration (ppm)

Primary Pollutants Secondary Pollutants 2 Sources NO NO2 SO3 Most hydrocarbons HNO3 H2SO4 Most suspended particles H2O2 O3 PANs SO4 2 – Most NO3 – and salts Natural Sources Stationary Mobile Figure 17-4 Page 421

March 10, 2000 March 12, 2000 March 13, 2000 March 15, 2000 Figure 17-5 Page 421

Ultraviolet radiation Solar radiation Ultraviolet radiation NO Nitric oxide O2 Molecular oxygen NO2 Nitrogen dioxide H2O Water O Atomic oxygen Hydrocarbons PANs Peroxyacyl nitrates HNO3 Nitric acid Aldehydes (e.g., formaldehyde) O3 Ozone Figure 17-6 Page 424 Photochemical smog

Formation of photochemical smog. Click to view animation. Animation

40 Nitric oxide Nitrogen dioxide Ozone 30 Parts per million 20 10 6 7 6 7 8 9 10 11 12 1 2 3 4 5 6 7 8 A.M. Noon P.M. Time Figure 17-7 (1) Page 425

Smoggy day Figure 17-7 (2) Page 425

Clear day Figure 17-7 (3) Page 425

Metallurgical dust and fumes Ultra Fine Particles Fine Particles Large Particles Sea salt nuclei Fly ash Carbon black Paint pigments Pollens Tobacco smoke Cement dust Milled flour Combustion nuclei Coal dust Oil smoke Metallurgical dust and fumes Photochemical smog Insecticide dusts Figure 17-8 Page 426 0.001 0.01 2.5 10.0 100.0 Average particle diameter (micrometers or microns)

Decreasing temperature Warmer air Inversion layer Increasing altitude Cool layer Mountain Mountain Valley Decreasing temperature Figure 17-9 (1) Page 427

Descending warm air mass Decreasing temperature Inversion layer Increasing altitude Sea breeze Mountain range Decreasing temperature Figure 17-9 (2) Page 427

Figure 17-10 Page 428 Wind Transformation to sulfuric acid (H2SO4) and nitric acid (HNO3) Windborne ammonia gas and particles of cultivated soil partially neutralize acids and form dry sulfate and nitrate salts Wet acid deposition (droplets of H2SO4 and HNO3 dissolved in rain and snow) Dry acid deposition (sulfur dioxide gas and particles of sulfate and nitrate salts) Sulfur dioxide (SO2) and NO Nitric oxide (NO) Acid fog Farm Ocean Lakes in shallow soil low in limestone become acidic Lakes in deep soil high in limestone are buffered Figure 17-10 Page 428

Acid deposition animation. Click to view animation. Animation

Figure 17-11 Page 429

Potential problem areas because of sensitive soils of air pollution: emissions leading to acid deposition Current problem areas (including lakes and rivers) Figure 17-12 Page 429

Percentage of direct sunlight intercepted Iran China Pakistan Saudi Arabia India Myanmar Arabian Sea Thailand Bay of Bengal Ethiopia Indian Ocean Equator Percentage of direct sunlight intercepted Very heavy 35%–45% Heavy 20%–35% Miles 1,000 Kilometers 1,600 Medium 10%–20% Figure 17-13 (1) Page 430

Winter Himalayas India Monsoons Cool, dry winds Summer Himalayas India Warm, moist winds Figure 17-13 (2) Page 430

Water boatman Whirligig Yellow perch Lake trout Brown trout Salamander (embryonic) Mayfly Smallmouth bass Mussel Figure 17-14 Page 431 6.5 6.0 5.5 5.0 4.5 4.0 3.5 pH

Emission Figure 17-15 Page 432 Acid deposition SO2 H2O2 PANs NOX O3 Others Increased Susceptibility to drought, extreme cold, insects, mosses, and disease organisms Direct damage to leaves and bark Reduced photosynthesis and growth Soil acidification Tree death Reduced nutrient and water uptake Leaching of soil nutrients Release of toxic metal icons Root damage Acid Figure 17-15 Page 432

Effect of air pollution in forests animation. Click to view animation. Animation

Prevention Cleanup Reduce air pollution by improving energy efficiency Add lime to neutralize acidified lakes Add phosphate fertilizer to neutralize acidified lakes Reduce coal use Increase natural gas use Increase use of renewable resources Burn low-sulfur coal Remove SO2 particulates, and NOx from smokestack gases Remove Nox from motor vehicular exhaust Figure 17-16 Page 433 Tax emissions of SO2

Para-dichlorobenzene Tetrachloroethylene Chloroform 1, 1, 1- Trichloroethane Formaldehyde Benzo-a-pyrene Nitrogen Oxides Styrene Tobacco Smoke Asbestos Radon-222 Carbon Monoxide Methylene Chloride Figure 17-17 Page 434

Outlet vents for furnaces and dryers Open window Openings around pipes Cracks in wall Slab joints Wood stove Cracks in floor Clothes dryer Furnace Radon-222 gas Sump pump Uranium-238 Slab Radium-222 Soil Figure 17-18 Page 436

Nasal cavity Oral cavity Pharynx (throat) Trachea (windpipe) Bronchus (see figure 17.18b) Trachea (windpipe) Bronchus Right lung Bronchioles (see figure 17.18c) Figure 17-19 (1) Page 437

Epithelial cell Cilia Mucus Figure 17-19 (2) Page 437

Bronchiole Alveolar sac (sectioned) Alveolar duct Alveoli Figure 17-19 (3) Page 437

Outdoor Exposure Developing countries (urban) 93% Developed countries Indoor Exposure Total deaths 0.2 million Developing countries (urban) 23% Developing countries (rural) 67% Developed countries (rural) 1% Developed countries (urban) 9% Figure 17-21 Page 438 Total deaths 2.8 million

Prevention Dispersion or Cleanup Burn low-sulfur coal Disperse emissions above thermal inversion layer with tall smokestacks Remove sulfur from coal Convert coal to a liquid or gaseous fuel Remove pollutants after combustion Shift to less polluting fuels Tax each unit of pollution produced Figure 17-22 Page 441

Cleaned gas Electrodes Dust discharge Dirty gas Figure 17-23 (1) Page 442 Electrostatic Precipitator

Bags Cleaned gas Dirty gas Dust discharge Figure 17-23 (2) Page 442 Baghouse Filter Dust discharge

Cleaned gas Dirty gas Dust discharge Figure 17-23 (3) Page 442 Cyclone Separator Dust discharge

Dirty gas Cleaned gas Clean water Wet gas Dirty water Figure 17-23 (4) Page 442 Wet Scrubber

Less polluting engines Improve fuel efficiency Prevention Cleanup Mass transit Emission control devices Bicycles and walking Less polluting engines Less polluting fuels Improve fuel efficiency Car exhaust Inspections twice a year Get older, polluting cars off the road Give buyers tax write- offs for buying low- polluting, energy- efficient vehicles Restrict driving in polluted areas Stricter emission standards Figure 17-24 Page 443

Figure 17-25 Page 443 Prevention Cleanup or Dilution Cover ceiling tiles and lining of AC ducts to prevent release of mineral fibers Use adjustable fresh air vents for work spaces Ban smoking or limit it to well- ventilated areas Increase intake of outside air Set stricter formaldehyde emissions standards for carpet, furniture, and building materials Change air more frequently Circulate building’s air through rooftop greenhouses Prevent radon infiltration Use exhaust hoods for stoves and appliances burning natural gas Use office machines in well-ventilated areas Use less polluting substitutes for harmful cleaning agents, paints, and other products Install efficient chimneys for wood-burning stoves Figure 17-25 Page 443